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An API, or Application Programming Interface, refers to a set of tools and protocols that is used by developers while building mobile applications. It is an excellent communication interface that facilitates interaction between various software applications. The sheer volume of the available APIs gives a fair idea about their popularity. These have shown phenomenal growth over the years, with as many as 15,000 of the searchable ones provided by ProgrammableWeb in 2016. More amazingly, the number of third-party APIs is growing with every passing day, giving developers the opportunity to get their projects to market faster than ever before.

APIs and Mobile Apps

APIs have seen a popularity boom since the beginning of the era of mobile apps. A large number of mobile apps integrate the user interface with device features and data via APIs. It can be rightly stated that APIs empower the application developers for creating amazing user-centric mobile apps with wonderful features and functionalities. For instance, these enable them to develop consumer apps that use geolocation for marketing purposes. Similarly, they can use specialized APIs to craft enterprise mobile apps that connect employees with the enterprise.

This is just the tip of the iceberg as the mobile app phenomenon is going to be huge, with almost half of the world population expected to be hooked on mobile apps in 2017. This is just one part of the picture as the future belongs to connected devices, with IoT penetrating into every aspect of human existence. The new era of communication is going to tap the true potential of APIs in the context of mobile apps and connected devices.

Popular Third Party APIs For Developers

APIs make a reliable tool for developers looking to create a context-aware mobile application. They do the vital task of syncing data with different services as well as making the apps interact with other apps. Developers have a choice between creating private APIs or integrating third-party APIs, which are available publically. The second option is preferred because it is cost-effective and offers greater flexibility as compared to the one built internally. Additionally, it gives access to a larger data set which creates a network effect. Moreover, developers can save time and effort, which can be invested in focusing on the core product or service they are offering.

Here are some of the most popular third-party APIs that are available for mobile app developers:

Google Maps API: A widely used public API, Google Maps makes use of a simple JavaScript/Flash interface to enable the embedding of Google Maps on the web pages. It has the capability to work on desktop browser applications, Android, and iOS devices. It provides language localization for more than fifty languages along with regional localization and geocoding.

Google Calendar API: This API is used to create, view, and modify public calendar events. It is also possible to access private calendars if the user is authorized to do so. Also, the API enables integration with Google Calendar and related objects such as access controls.

Google Analytics API: Another popular choice is Google Analytics API, which facilitates the customization of tracking data for the website or mobile app. The data collected can be analyzed and configured to reach the relevant audience.

YouTube Data API: With YouTube Data API, the developer is able to add the functionality of YouTube to the mobile app. This encompasses the diverse YouTube features such as video uploads, channel setting updates, and management of subscriptions and playlists.

Facebook API: Social is the rage today and mobile apps can be enhanced in the social context with the help of Facebook API. It is used to integrate top-end features of the platform in the mobile application.

Twitter API: Like Facebook API, Twitter API also gives the social edge to mobile applications. Developers can use it for accessing the core Twitter data, along with features like user information, update timelines, and status data.

Instagram API: Instagram is a much-loved photo sharing app which is a rage amongst the tech-savvy mobile users today. With Instagram API, developers are able to get access to the various elements of Instagram, such as user authentication, photos, friend connections, and etc.

Weather API: As the name suggests, WeatherAPI provides data related to the real-time weather condition at more than 200,000 cities across the globe. The data is contributed and constantly updated by as many as 40,000 weather stations situated at different global locations.

LinkedIn API: LinkedIn is a renowned professional networking site that has thousands of members across the world. Since the platform is used for professional purposes, its API offers business applications such as content sharing and certification posting.

Google+ API: Developers can use Google+ API to create an engaging experience for the app users. The API integrates social into mobile apps so that the users can connect with more fellow users with the app.

The variety in third-party APIs is immense but the real challenge lies in their integration. Certain best practices are to be followed when using these APIs to build a secure mobile application:

Primarily, the documentation should be examined thoroughly so that the API can be used to its full potential. The documentation also gives complete information related to the data input, data output, usage restrictions, and other implementation details.

Only APIs which come from reputable sources and are well-tested in the context of the user experience they offer should be used. The ones which deliver poor user experience are better left alone.

Scalability is important too as a business is likely to grow over time and the API should be capable of aligning with its growth.

It should also have robust security features so that the risks of data theft and hacking are reduced to the minimum. Again, relying on legitimate sources is a good idea to get secure data protection with the chosen API.

Developers not only need to follow the latest UI design trends to make an app successful, but they must also add wonderful functionalities to it. This is where APIs come into play. The significance of APIs for mobile applications is unmatched as these act as a lifeline for them. A mobile app is comparable to a human body, while APIs are similar to veins and arteries which keep the blood supply running in the body. Therefore, developers should focus on the smart integration of relevant APIs to fuel the app they create.

Analysts agree that a mix of emulators/simulators and real devices are necessary to optimize your mobile app testing - learn more in this white paper, brought to you in partnership with Sauce Labs.